locale: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On CentOS possible default full paths are:

/usr/bin/locale - from package: glibc-common

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/bin/locale - from package: libc-bin

You may install the required package with command apt-get install {package}

Error in other languages:
locale: bevel nie gevind nie
locale: comandă negăsită
locale: comando não encontrado
locale: commande introuvable
locale: command not found
locale: käsku ei ole
locale: không tìm thấy lệnh
locale: komanda nerasta
locale: Kommando nicht gefunden.
locale: kommandot finns inte
locale: komut yok
locale: nie znaleziono polecenia
locale: níor aimsíodh an t-ordú
locale: no se encontró la orden
locale: no s'ha trobat l'ordre
locale: opdracht niet gevonden
locale: parancs nem található
locale: perintah tidak ditemukan
locale: príkaz nenájdený
locale: příkaz nenalezen
locale: команда не найдена
locale: командата не е открита
locale: 命令找不到
locale: コマンドが見つかりません